Vehicles powered by internal combustion engines are provided with exhaust systems connected to the exhaust ports of the engine. The design of the exhaust system has an effect on the power output of the engine, the noise level and sound signature generated by the engine. The exhaust system also assists in controlling the pollution generated by the engine. However, the design choices for an exhaust system that maximizes power output are generally contradictory to the design choices for an exhaust system that minimizes noise level and optimizes sound signature. A reasonable trade-off therefore has to be reached in the design.
In order to maximize power, it is known to have long exhaust pipes connected to the exhaust ports. In order to minimize noise, it is known to include expansion chambers such as resonator and mufflers in the exhaust system. Long exhaust pipes and expansion chambers take a lot of room in a vehicle.
In many vehicles, such as off-road side-by-side vehicles (SSVs), the amount of room available for the various vehicle components is limited. In a SSV for example, the cockpit area has low seats, therefore providing very little room for components under the seats, and most of the remaining volume has to be free in order to accommodate the riders of the vehicle. The portions of the SSV forward and rearward of the cockpit area are relatively short and mostly occupied by the drive train and suspension components (and steering components at the front), thus leaving little room for other components. Also, in view of the operating conditions of SSVs, typically rough, unpaved terrain, designers of SSVs try as much as possible not to have any components extending below the frame of the vehicle as these could get damaged. As such, there is not a lot of room to place components of an exhaust system, especially one with long exhaust pipes and expansion chambers.
There is therefore a need for an exhaust system for a vehicle which provides an acceptable trade-off between engine power output and noise level while fitting in a limited amount of space.